Punch press



A ril 9, 1935. v. A. BOKER 1,997,292

PUNCH- PRESS Filed July 22, 1935 2 Sheets-Sheet 1 t a n Fiji-Iva April1935. v. A. BOKER 1,997,292

PUNCH PRESS Filed July 22, 1935 2 Sheets-Sheet 2 m 1mm m r 41. 3o 4 2943 45 Wfm v 40 the die plateremoved therefrom;

Patented Apr. 9, 1935 V i i I 7 UNITED STATES PATENT OFFICE gPUNCH'PRESS Vitus A. Boker, Minneapolis, Minn. Application July 22,1933,Serial No. 681,727

fiClaims. (01.164-110) My present invention relates to punch presses,movements in vertical guides I? of said frame; and provides certainhighly important improve-, and the numeral l8,'the connecting rod thatments therein, to wit: an improved self-stripconnects the eccentric ofthe crank shaft 15 to ping die set; and an improved means for sup saidram IS. The bedplate I4 is provided with 5 porting die plates, all aswill hereinafter more one or more suitable slug passages l9, which, in'5- fully appear. the particulararrangement illustrated in Fig; 2,

Generally stated, the invention consists of the is divided into twochannels by a partition 20, novel devices, combinations of devices andarwhich latter feature, however, constitutes no rangement of partshereinafter. described and part of the present invention. v

.defined in the claims. r v Rigidly seeuredon the bedplate M, by meansof 10 The invention is here illustrated in connection machine screws 2|or the like, is a die plate supwith a' punch press of standardconstruction of porting shoe 22 that spans theopening ISand is the typewherein movement of the power-acprovided withaslugpassage oropening'23that tuated ram is controlled by a foot treadle, but the will permit thedropping a of slugs through .the

invention, of course, may be applied to any suit-. openings |9.- Theshoe 22 has a raised portion 15 able type of press. that. is formed withlongitudinal dove tailed Referring to thedrawings, wherein likecharchannel that receives and slidably holds one or acters indicate likeparts throughout the several more supplemental die supports in the formof views: H v V I a rectangular. metallic blocks 24 having projectingFig. 1 is. a perspective showing the press studs or knobs 25. Theseblocks 24 slide fric- 20 equipped in accordance with my invention;tionally in the channel of theshoe and when Fig. 2 is a fragmentary viewon a larger scale properly positioned, are adapted to be rigidly thanFig. 1, showing partly in front elevation and held'where set by setscrews 26 applied through partly in section the principal parts of thepress, .the'proper threaded perforations 26 of the shoe,

to wit; the rain, the punch holder, punch pad, as best shown in Figs.,7, 8 and 9. The important 25 stripper plate, die plate, shoe and'bed ofthe purposeof these supplemental diesupports will press; q appear in thedescription of the operation and Fig. 3 is a View correspondingtolFigy2, but use of the invention. a j with different positions of theparts and with the The die, which usually is in theform of a flat shoe,dieplate and bed omitted; tempered steel plate 21, is rigidly secured onthe 30 Fig. 4 is a horizontal sectiontaken on the .line top of the shoeby meansof screws 28 or the like 44 of Fig.3; r f A andspans thechannelof the shoe. This die plate Fig. 5 is a perspective showing the punch isshown as provided with die openings 29 and 30 holder and stripper plateremoved from theram; with a stock guide3 l; and a stop pin 32, ,but, of4 Fig. 6 is a fragmentary section taken on the course, saidplatemay takedifferent. forms, as '35 line 66 of Fig. 5.; v required "for punchingout work of different Fig. 7 isaperspective showing'the shoeof designs.f the press'with the die plate applied thereto; The vertically movableramlB above noted, at

Fig. 8 is a perspective showing the shoe with its lower end, has anaxial bore adapting it to Y receive the tubular shank 33 of a punchholder Fig. 9 is a section taken on the line !l9v of or head 34. Tofirmly clamp the shank. 33, said Fig. 8; j H i ram at its lower endissplit and provided with Fig.- 10 is a transverse section illustrating aa clamping segment lfi clamped-thereto by nutmodified form of the shoe;equipped studs IB as best shown in Fig. 4.

Fig. 11 is atransverse section illustrating a Above the clamp l 6, theram is formed with dia- 45 shoe with modified form of die plate support;metrically, offset vertically extended slots 35 and 2 through which isextended "a knock-out bar 36 Fig. '12 is apersp'ective showing thedieplate that is capable of limited vertical movements in of Fig. 11'removed from the shoe. said slot, but is held'against endwise displace-The preferred structure illustrated in Figs. 1 "ment by suitable devicessuch as splitkeys or 50 to 9, inclusive, will first be described. Of thecutters 31, see particularly Figs, 2 and 3. The principal parts of thepress illustrated, the punchholder 34 is formed with atransverse 1on5numeral 13 indicates the framework; the nugitudinal slot 38 throughwhich is extended a meral 14, the bedplate; l5, thepower-driven stripperbar 39 that is capable of limited ver- 1' ,5i crank shaft; l6, the rammounted for vertical tical movements insaid slot. The numeral 43 and 44may be anchored inthe punch pad in various different ways, butpreferably they are so anchored by casting matrix metal or the like,

(which does not perceptibly expand or contract under varyingtemperatureh, indicated; at, 45,,

around the same with heads or upper ends of said punches seated directlyagainst said punch pad. Of course, the particular arrangement: of; the

punches in the punch pad and of the die pas-- sages in the die plateWill vary according to the designof the article to be punched.

The stripper plate 46, which is immediately belowthe punch pad, haspunch passages that correspond to and freely pass the punches 43 and 44.Loosely surrounding andv vertically movable on the punch holder or head34, is a stripper frame 4"! through which the ends of the stripper bar39 projects so that said bar andstripper frame will partakeof commonvertical movenients. This stripper frame 41' is normally locked to thestripper plate 46 by suitablemeans such as spring-pressed latches 48shown as pivoted'to the projecting end of stripper bar 39 and providedat their depending ends with hooked lugs that engage and interlock withseats on the end of the stripper plate, formed by brackets 43secured; tosaid; stripper plate at the ends thereof,

that project beyond the stripper frame,- see particularly Figs. 2, 3 and'5.

p When the ram andparts carried thereby are raised, as shownin Fig. 3,the projectingends of the knock-out bar 36 will engage thelower ends ofstops afforded bylstop screws 51}, mounted for vertical adjustments inlugs 5 l onthe Ver- ,tical guides 11". Fromthe foregoing, it is evidentthat the punch pad with its punches m-ay be readily removed from thepunchhol'derand other punch pads with punches properlyarranged forco-operation witha substituted die plate. may be applied to said punchholder. To effect such substitutions requires that thestripper plate beremoved; and this obviously may be very quickly accomplished'byreleasing the spring latches 48. In making the above substitutionsand-at certain other times, it is desirable to hold the-stripper frame41 in a raised position, and sometimes this may be desirable evenwhen'the" stripper plate is; left in operative position; and this may beaccomplished by inserting a lock pin 52'" in coincident holes 53 and 54formed respectively,

in the punch holder and stripper frame, see particularly Figs. 5.and 6.

. The sheet of metal from which the articles are to be. punched, andwhich is herein designated as the stock or stock sheet, is indicated bythe character y.

' Operation in setting the punching apparatus for use, the

auxiliary diesupporting blocks 2 lwill be adjust- "ed so that theirstuds or projections will be engaged with the under side of the die'plateiat various weak points, such as points between die openings or punchpassages. A good adjustment Rigidly seated in oozzez of said auxiliarydie-supports is illustrated in Fig. 2.

When the ram is raised, the stripper plate, stripper frame, stripperbar, knock-out pin and knock-out bar will, under the action of gravity,tend to assume lowered positions in which the lower surface of thestripper plate will be slightly below the lowerends of the punches.Under the punching action, the stripper plate will come into contactwith the stock strip or sheet, slightly in. advance of the punches, andwill be gravityheld against the sheet while the punches are positivelyforced through the sheet. Under upward movement of the ram, the stocksheet will be frictionally held on the punches and carried upwardtherewith until the knock-out bar 36 comes into engagement with the stopscrew 50, and thereupon, under the slightly continued up- 7 wardmovement of the ram, punch holder, punch In Fig. l0,there is illustrateda scheme for fpositivelypreventing lateral spring or spreading of wideshoes. In this structure, the wide shoe is indicated by-55, transverselythrough the sides of which is extended one ormore nut-equipped bolts 58;In this arrangement, the auxiliary die-supporting block 5'! .is providedwith a plurality of die-engaging studs or projections 58.

Fig. 11 illustrates a modified form of auxiliary die support wherein thedie-supporting blocks 59 are providedwith hubs seated in the sides ofthe shoe Stand held in position by machine screw 6!. The form ofauxiliary die support illustrated in Fig. 111 is especially designed tosupport inwardly projected lug-like portions of a die plate, such asbest shown in Fig. 12 and also in Fig. 11. This die plate'62, it willbenoted, is formed with inwardly projecting lug-like portions 63 thatare adapted to be supported by underlying locks 59.

From the foregoing, it will be understood that thefdev ices abovedescribed are capable of various modifications within the scopeof theinvention herein disclosed and claimed. The practicability andefliciency of the devices herein disclosed and claimed, as well as thecheapness of manufacture','h'ave been demonstrated in actualpractice. Afurther advantage in making thedies under this system may be'found to bea great saving of space in storing.

-WhatIclaimisi.

. .1. .In a punchpress, the combination with the I reciprocatory ramthereof and a punch-equipped holder carried by said ram, of a stripperframe having limited sliding movements on, said punch holder, a stripperplate detachably attached to said stripper frame and having openingsthrough which the punches work, and means operative under recedingmovement of said ram to intercept- 'receding movement of said stripperframe and thereby cause said stripper-plate to strip the punched stockfrom the punches.

' 2. The structuredefined in claim 1 in further combination with latchesfor quickly attaching said stripper-plate to and; quickly" disconnectingthe same from said stripper frame.

3. In a punch press, the combination with the reciprocating ram thereofand a punch-equipped holder carried by said ram, of a stripper framehaving limited sliding movements on saidpunch -ho1der,j'a stripper barextended through 'said punch holder and stripper frame and connected formovements with said frame, a stripper plate having openings throughwhich said punches work, means on the outer ends of said stripper barfor connecting said stripper plate to said stripper frame, stop meansrelatively fixed on the punch frame, and knock-out elementsintermediate-said stripper bar and stop means operative under recedingmovement of said ram to cause said stripper plate to strip the stockstrip from the punches. r

4. In a punch press, the combination with the reciprocating ram thereofand a punch-equipped holder carried by said ram, of a stripper framehaving limited sliding movements on said punch holder, a stripper barextended through said punch holder and stripper frame and connected formovements with said frame, a stripper plate having openings throughwhich said punches work, means on the outer endsof said stripper bar forconnecting said stripper plate to said ram to cause said'stripper plateto strip the, stock sheet from the punches.

5. The structure. defined in claim 3 in which the means on'the outerends of the stripper bar for connectingsaid stripper plate to thestripper frame are yieldingly heldlatchesr 6. In a punch press, thecombination with the reciprocating ram thereof and a punch-equippedholder carried by said ram, of a stripper'frame having limited slidingmovements on said punch holder, a stripper bar extended through saidpunchholder and stripper frame and connected for movements with saidframe, a stripper plate -having. openings through which said puncheswork, means on the outer ends of said stripper bar for connecting saidstripper plate to said stripper frame, a knock-out bar extendeddiametrically through and projected from said ram, a knock-out pininterposed between said knockout bar and stripper bar; and laterallyspaced stop devices on the frame of said press adjacent saidram andagainst which the-projecting ends of said "knockout-bar are engageableunder extreme receding movements of said ram to'cause said stripperplateto strip the stock sheet from the punches. Y c vrrus A. BOKER.

